Table 1

Summary of areas receiving potential synaptic input from the NI

Olfactory area
    Anterior olfactory n.AO+ Figure 10B
    Cerebral cortex
    Cingulate cortexCg++ Figure 10C,P,S
    ClaustrumCl+ Figure 10F,M
    Dorsal peduncular cortexDP+ Figure 10I
    Infralimbic cortexIL+
    Orbital cortex, medialMO+
    Prelimbic cortexPrl+ Figure 10C
    Retrosplenial cortexRS++ Figure 11G
    CA1 field, oriens layerCA1+ Figure 11C
    CA2 field, oriens layerCA2+ Figure 11C
    CA3 field, oriens layerCA3+
    Dentate gyrusDG+
    Dorsal tenia tectaDTT++ Figure 10E
Nucleus diagonal band
    Horizontal limbHDB++
    Vertical limbVDB+++ Figure 10H,L
    Lateral septal n., dorsalLSD+ Figure 10 I,Q
    Lateral septal n., intermediateLSI++ Figure 10H,L,Q
    Medial septal n.MS+++ Figure 10H,I,K
    Septofimbrial n.SFi+
    Triangular septal n.TS+
    Zona incertaZI+ Figure 11B
    Lateral hypothalamic areaLH+++ Figures 10T, 11B,F
    Posterior hypothalamic areaPH++ Figure 11F
    Preoptic area, lateralLPO+++ Figure 10O
    Supramammillary n.SuM+
    Dorsal raphe n., dorsal partDRD+ Figure 11R
    Dorsal raphe n., inferior partDRI++ Figure 11P,R,S
    Interpeduncular nucleus1 IP+/− Figure 11I,K
    Rostromedial tegmental n.2 RMTg+++ Figure 11K
    Ventral tegmental area3 VTA+/− Figure 11I,K
    Periaqueductal grayPAG+ Figure 11N
    Central gray, pontinePnO++ Figure 11M,P,S
    Median raphe n.MnR+ Figure 11M,P,S
    Nucleus incertus (cell bodies)NI/O+++ Figure 7
    Paramedian raphe n.PMnR+++ Figure 11M,P,S
    Anterior tegmental n.4 (caudal RMTg)ATg++ Figure 11M
  • The NI of Rln3Cre mice was injected with a mixture of Cre-dependent AAV-expressing sypGFP and tdT as shown in Figure 7, strategy 2. The summary is based on the case appearing in Figures 10, 11, but further supporting data were derived from the case shown in Figures 12, 13, and injected cases not shown. The density of afferents from the NI was scored from + to +++ based on the appearance of punctate sypGFP fluorescence, which is consistent with presynaptic labeling. The designation +/− is reserved for areas in which tdT-labeled fibers were observed, but little or no sypGFP, suggesting labeled fibers of passage. No consistent Rln3Cre -dependent labeling was observed in areas caudal to the pons.

  • 1 Labeled fibers appear immediately adjacent to the IP, but little synaptic labeling is seen within the nucleus.

  • 2 The rostromedial tegmental nucleus is not defined in standard atlases (Paxinos and Franklin, 2001) but resides just dorsolateral to the IP; this area is known to send GABAergic input to the VTA (Quina et al., 2015).

  • 3 sypGFP labeling is defined within the VTA as anatomically defined, but it does not appear adjacent to DA neurons in this area.

  • 4 The area defined as the anterior tegmental nucleus in standard atlases has been shown to contain neurons with similar properties to the RMTg, and has been labeled the caudal RMTg (cRMTg, Quina et al., 2015).